If you have been an advocate of fine tuning the autofocus of your lenses with your camera bodies for more than a year, then you know that alternatives for that fine tuning has changed dramatically since 2011. Before 2012, the defacto standard for tuning autofocus was the LensAlign system published by Michael Tapes. Many professional photographers have used his tuning kits for years, and some still use it.

If you go to Amazon.com and search for LensAlign MkII Focus Calibration System, you will find what folks have said about LensAlign. Over half of the reviewers liked the kit and found it useful in fine tuning their lens to their camera bodies. However, there were a significant number of buyers who did not like the kit. Many had difficulty assembling and using the kit, or they found the results unreliable. My guess is that many of the unhappy users simply did not use the kit as it was designed to be used.

Now those unhappy users have other alternatives that should provide them with better results. In 2011, Reikan Technologies published the FoCal software system for fine tuning Canon bodies with lens. By mid-2012, they had added Nikon support to that system although they never bothered to completely update the user manual to include Nikon nomenclature. The software also contained many bugs that would cause it to crash in the middle of tests requiring the user to start over. A typical user would perform an average of 200 clicks with a camera and lens to get a reliable calibration.

By the fall of 2012, the Reikan folks had made significant improvements in FoCal and Michael Tapes had published FocusTune to compete with FoCal. While the Reikan folks had the patience to deal with the software development kits (SDK) from Canon and Nikon to produce a tuning system that worked directly through the camera bodies via a USB connection, Michael Tapes took a completely different tack with the development of his FocusTune software. He basically automated the review of images that you would normally capture during a fine tuning procedure with LensAlign by writing computer software that analyses the captured images from either the LensAlign kit or a target that he provides with the software.

So now you have two software-driven alternatives for fine tuning a lens with a Nikon or Canon camera body. You can either run FoCal while tethered to your camera or you can capture the same type of images with your camera/lens that you take with FoCal, load them into an off-line computer and have FocusTune analyze those images. Either way, you should get better autofocus fine tuning results than you were getting with either the LensAlign kit or through other manual tuning procedures because a computer is reviewing the sharpness of your captured images and recommending the final autofocus setting for your camera/lens combination.

Your choice of which software tuning kit to buy will depend on how much hand holding you want the kit to do for you and how much control you want of the data analysis. Because FoCal runs in a computer that is tethered to the camera you are testing, it can monitor your testing operation and point out ways to improve the results. For example, the software can review your tuning target and tell you if it is positioned properly for good test results. FoCal also allows you to change the camera’s ISO in order to increase test shutter speeds to get better results for long lens, and it will tell you if the target is not illuminated well enough for dependable results.

Since FocusTune runs in a computer that is not tethered to the camera you are testing, you are completely in control of the test conditions. You have to carefully read all FocusTune testing documentation to be sure you are performing the testing properly. Assuming you follow the procedures correctly, the software will give you all of the information you need to adjust the autofocus of your camera with each lens you test. FocusTune also has the flexibility to let you add or reduce test shots that you take as part of the testing.

One of the key FoCal features for Canon owners is the ability to completely automate the process of autofocus fine tuning (micro focus adjustment). Because Canon publishes more controls in their SDK than Nikon, Reikan was able to provide more complete automation of the tuning with some Canon bodies. With Nikon bodies, the user has to participate in the fine tuning by making the fine tuning adjustments in between each test shot FoCal makes.

In addition to autofocus fine tuning, both FoCal and FocusTune allow you to perform several other tests. If you are willing to do the camera clicks or let the software execute them for you in the case of FoCal, the software kits can provide you with insight into the following:
- Autofocus reliability
- Lens sharpness by aperture
- Sensor dust analysis

FoCal goes one step further by letting you test the sharpness of every focus sensor in your camera. This is particularly good if you suspect that some autofocus sensors are not performing as well as others as was the case with some early copies of the Nikon D800.

One last item of note is pricing for these software alternatives. While you will pay $79 - $99 for FoCal Pro, you can buy FocusTune for as little as $19 if you already own LensAlign. If you are price sensitive, you could start with FocusTune and move on to FoCal if you feel you still need tuning refinement.

I will talk about the time it takes to use these two systems and tips for using them in another posting.